Live Pole Drains (LPDs) are a plant-based drainage system used to drain natural slopes and prevent shallow gully erosion. LPDs are a Nature-based Solution built by placing a live fascine in a shallow ditch or gully along the slope direction, allowing moderate fluxes of surface runoff or seepage to infiltrate and high water fluxes to be conveyed along the fascine without further eroding the slope. Despite their practical implementation, the transient and long-term eco-hydrological behavior of LPDs is not well understood. We aim to better understand the LPD’s water balance, the seasonal and life-span changes in hydrological behavior, as well as the impact of an LPD on surface runoff water quality. To this end, we built and instrumented an artificial slope with full-scale LPDs in an open-air lab (OAL) at TU Delft. The design of the setup and the monitoring plan of the LPDs were developed in collaboration with Glasgow Caledonian University with insights from the construction and monitoring of three LPDs at different growth stages in their OAL on the east coast of Scotland. Herein, the design and possible research experiments that can be performed over the next 5 years are presented, generating a data set to further develop and validate hydrological modeling of LPDs. We expect this long-term demonstrative setup to generate interest and facilitate a more comprehensive understanding of LPD functions, ultimately leading to the incorporation of LPD design and maintenance standards in engineering toolboxes for slope and gully stabilization.

This project is a consulting project for Community Cloud Forest Conservation (CCFC) on how to obtain and communicate to relevant stakeholders an understanding of the impact of land use change and climate change on the hydrological balance of the cloud forest ecosystem in the Sierra Yalijux. The outcomes of the project will be used by CCFC and partners in four areas: Rural water committee capacity building with municipal and village leadership groups, environmental education with the ministry of education, reforestation, and conservation carbon/water credit prioritization with the national forestry institute, and to create thesis topics for bachelors level students with Universidad Rafael Landívar and Universidad de San Carlos. In order to achieve this goal, we divided our efforts in four areas: First, a description of the situation and a review of literature to identify gaps in scientific and practical understanding of local cloud forest hydrology (Chapter 2). Second, an analysis of the situation at a regional scale using publicly available historical data such as remote sensing data and data from the national meteorological authority (Chapter 3). Third, identifying important hydrological processes in the Cloud Forest micro-climate (Chapter 4) and prototyping and testing measurement setups (Chapter 5). Fourth, making suggestions on how to apply the results to the intended impact areas that CCFC has (Chapter 6). Our recommendations to CCFC for capacity building with water committees are based on a literature re view, we found that the presence of Cloud Forest is expected to increase base flow in springs due to its ability to capture additional hydrological inputs in the dry season, increase moisture recycling after heavy rain events, and store water in the soil. We recommend working with water committees to outline the recharge zones of their springs, run some simple calculations on water availability based on precipitation, and develop manage ment plans for the area. Our recommendations for further research are based on the research approaches we describe at the regional scale and the prototyping of field methodologies that we tested. A more permanent setup for data collection is being developed jointly with the Universidad de San Carlos at CCFC’s nature preserve.